The recovery of base metals from sulphide ores by bacterially assisted heap leaching is presently restricted to secondary copper sulphide minerals, such as chalcocite and covellite. Chalcopyrite, a primary copper sulphide mineral, is a notable exception and can not presently be successfully leached in a heap. There is currently no proven method available for the successful bacterially assisted heap leaching of nickel sulphides, zinc sulphides or any other base metal sulphide except those of copper, excluding chalcopyrite.
The bacterially assisted heap leach of the present invention has as one object thereof to overcome the problems associated with the prior art, or to at least provide a useful alternative thereto.
The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was part of the common general knowledge in Australia as at the priority date of the application.
Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.